.\" Copyright (c) 2014 The FreeBSD Foundation
.\"
.\" This software was developed by Edward Tomasz Napierala under sponsorship
.\" from the FreeBSD Foundation.
.\"
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.Dd December 2, 2017
.Dt AUTOFS 4
.Os
.Sh NAME
.Nm autofs
.Nd "automounter filesystem"
.Sh SYNOPSIS
To compile this driver into the kernel,
place the following line in the
kernel configuration file:
.Bd -ragged -offset indent
.Cd "options AUTOFS"
.Ed
.Pp
Alternatively, to load the driver as a
module at boot time, place the following line in
.Xr loader.conf 5 :
.Bd -literal -offset indent
autofs_load="YES"
.Ed
.Sh DESCRIPTION
The
.Nm
driver is the kernel component of the automounter infrastructure.
Its job is to pass mount requests to the
.Xr automountd 8
daemon, and pause the processes trying to access the automounted filesystem
until the mount is completed.
It is mounted by the
.Xr automount 8 .
.Sh OPTIONS
These options are available when
mounting
.Nm
file systems:
.Bl -tag -width indent
.It Cm master_options
Mount options for all filesystems specified in the map entry.
.It Cm master_prefix
Filesystem mountpoint prefix.
.El
.Sh SYSCTL VARIABLES
The following variables are available as both
.Xr sysctl 8
variables and
.Xr loader 8
tunables:
.Bl -tag -width indent
.It Va vfs.autofs.debug
Verbosity level for log messages from the
.Nm
driver.
Set to 0 to disable logging or 1 to warn about potential problems.
Larger values enable debugging output.
Defaults to 1.
.It Va vfs.autofs.interruptible
Set to 1 to allow mount requests to be interrupted by signal.
Defaults to 1.
.It Va vfs.autofs.retry_delay
Number of seconds before retrying mount requests.
Defaults to 1.
.It Va vfs.autofs.retry_attempts
Number of attempts before failing mount.
Defaults to 3.
.It Va vfs.autofs.cache
Number of seconds to wait before reinvoking
.Xr automountd 8
for any given file or directory.
Defaults to 600.
.It Va vfs.autofs.timeout
Number of seconds to wait for
.Xr automountd 8
to handle the mount request.
Defaults to 30.
.It Va vfs.autofs.mount_on_stat
Set to 1 to trigger mount on
.Xr stat 2
on mountpoint.
Defaults to 0.
.El
.Sh EXAMPLES
To unmount all mounted
.Nm
filesystems:
.Pp
.Dl "umount -At autofs"
.Pp
To mount
.Nm
filesystems specified in
.Xr auto_master 5 :
.Pp
.Dl "automount"
.Sh SEE ALSO
.Xr auto_master 5 ,
.Xr automount 8 ,
.Xr automountd 8 ,
.Xr autounmountd 8
.Sh HISTORY
The
.Nm
driver first appeared in
.Fx 10.1 .
.Sh AUTHORS
The
.Nm
was developed by
.An Edward Tomasz Napierala Aq Mt trasz@FreeBSD.org
under sponsorship from the FreeBSD Foundation.
